The present invention relates to ignition mechanisms and devices containing such ignition mechanisms, such as, for example, lighters, including pocket and extended wand type lighters, disposable and non-disposable lighters, and, more particularly relates to piezoelectric ignition mechanisms and piezoelectric lighters, including particularly such ignition mechanisms and lighters that present increased resistance to operation by unintended users.
Disposable gas lighters are available in a variety of forms. Typically, one common element of disposable lighters is an actuator pad or lever used to initiate the flow of fuel. An actuator pad is typically operated in conjunction with a spark producing mechanism so that the flow of fuel is ignited soon after it commences. For example, one type of lighter requires a user to rotate a toothed spark wheel against a flint in order to generate a spark, while, or immediately followed by, depressing the actuator pad to release gas and produce a flame.
Other means of ignition for disposable lighters employ a piezoelectric mechanism. In this type of ignition mechanism, a piezoelectric element, such as a crystal, is struck by a hammer in order to produce an electric spark. The spark is created at the fuel outlet or nozzle to ignite the gaseous fuel. The actuator button, upon forced depression by a user, typically commences both the flow of the fuel and then the ignition process. An example of such a piezoelectric ignition mechanism is disclosed in U.S. Pat. No. 5,262,697, entitled xe2x80x9cPiezoelectric Mechanism For Gas Lighters.xe2x80x9d
Measures have been introduced to make activation of lighters more difficult or resistant to operation by unintended users. One typical method employed is to incorporate a latch member that inhibits depression of the actuator pad. Examples of such mechanisms are shown in U.S. Pat. Nos. 5,435,719; 5,584,682, and 5,636,979.
There remains, however, a need in the art for ignition mechanisms and lighters which increase the difficulty of inadvertent operation or undesirable operation by unintended users, and at the same time are user-friendly and appeal to a variety of intended users.
The present invention relates to a piezoelectric ignition mechanism which presents increased difficulty of operation by unintended users, and lighters, including pocket or extended wand type lighters that incorporate the same. In one embodiment, the ignition mechanism includes an assembly having first and second members which are slidable and rotatable with respect to one another about their common longitudinal axis. A piezoelectric element is positioned on the assembly, and a plexor is associated with, preferably located inside, the assembly. The assembly is rotatable between an activated and a deactivated configuration. When in the activated configuration, the plexor is capable of striking the piezoelectric element with sufficient force to produce a spark. Preferably, an impact spring is associated with one end of the plexor and is compressed by the plexor, the impact spring capable of driving the plexor, when in the activated position, with sufficient force to generate a spark. When in the deactivated configuration, the spring may not compress or be sufficiently compressed to drive the plexor toward the piezoelectric element to cause it to produce a spark.
The plexor preferably includes a lug disposed on its side that is received by a longitudinal slot defined on the first member. The first member may further have a notch associated with the longitudinal slot that is capable of receiving the lug. When the assembly is in the activated configuration, the lug may be moved into the notch and compressed against the impact spring. A window is defined in the second member and has a side portion. When the assembly is in the deactivated configuration, the side portion may contact the lug and block it from entering the notch. The window may further define a ramp portion, such that when the assembly is in the activated configuration and the first member is moved a predetermined distance toward the second member, the lug engages the ramp portion of the window, which rotates the plexor until the lug is released from the notch and is moveable within the longitudinal slot. More than one lug may be provided on the plexor, and more than one longitudinal slot and more than one notch may be provided in the first member. The second member also may have more than one window with more than one side and ramp portions.
In one embodiment, an abutment may be disposed on the first member and a cam may be disposed on the second member, wherein the cam is dimensioned to interact with the abutment when the first member is depressed toward the second member, such that the assembly is rotated to the deactivated configuration. Alternatively, the abutment may be disposed on the second member and the cam may be disposed on the first member. The abutment may be a portion of a push button associated with the first or second member.
In a further embodiment, the ignition mechanism includes an arm disposed on the second member for rotating it with respect to the first member, and the cam is disposed on the first member. The cam is dimensioned to bias the arm upon substantial depression of the first member such that the assembly is rotated to the deactivated configuration. Alternatively, the arm may be disposed on the second member and the cam may be disposed on the first member.
The present invention is also directed to a lighter incorporating the ignition mechanism. The ignition mechanism may be located in a lighter body having a fuel reservoir and which may have a valve for selectively releasing fuel. In one embodiment, the lighter body has an aperture defined therein, and an arm disposed on the ignition mechanism protrudes through the aperture to allow rotation of the first or second members therein with respect to one another.
The present invention is further directed to a utility lighter incorporating the ignition mechanism. The ignition mechanism may be located inside a housing having a handle, a fuel supply, and an extended wand having a nozzle for selectively releasing fuel. In one embodiment, an arm is connected to the ignition mechanism and the arm passes through an aperture provided in the housing. Rotation of the arm allows a user to rotate the first and second members with respect to one another within the housing, thus rotating the members between the activated and deactivated configurations. Preferably, the aperture is configured and dimensioned to bias the arm such that the plexor is automatically rotated to the deactivated configuration after the members are moved toward one another a predetermined distance.